I would recommend running mount -a instead of mount /mnt/backup, as it will let you know if there are any errors in your fstab file after your edit. Otherwise, if there are errors, you won't know about it until your next boot and you may have to boot from a live cd to fix it.
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tj111Aug 18 '10 at 16:06

Thank you very much. This isn't quite what I'm looking for (also removing the volume from the Places nautilus sidebar) however now I think about it I'm not sure I need it in that sidebar!
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8128Aug 18 '10 at 17:15

What I did afterwards was went to each location and added a bookmark. They now appear at the bottom of the list so you don't miss anything.
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Richard HollowayAug 18 '10 at 18:48

Part 1 of the line is what to mount, part 2 is where to mount it, part 3 is file-system type, part 4 is mount options (add noauto if you don't want it to be mounted automatically) make sure that the user and owner options are not set!, part 5 is whather to dump the file-system if errors occur, and part 6 is the order in witch fsck will check the file systems.
Part 5 is always 0 (unless you know what you are doing) and part 6 is 0 for non-native volumes (ie. ntfs, vfat etc.), 1 for root file-system and 2 for everything else (mainly ext2, ext3, ext4).

So the UUID of sda1 is 7244DE9322DE5A05, sdb1 is f6245825-06dc-4c97-87d3-dbe3c943247d and so on..
Now to find out what volumes are the ones that you want to add you can just mount them (by double clicking on the desktop icon) and the type mount in a terminal, this will list what is currently mounted where.

If I'm reading the source right, volumes from fstab are shown except if they are not user mountable OR loopbak OR the string "/vol/" is not in the volume path. Flutefute check that your fstab doesn't include the user option in it's line. Source code on gnome-vfs2.sourcearchive.com/lines/2.8.4/… search for create_drive_on_mount_point
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Javier RiveraAug 18 '10 at 10:53